Apparatus for associating objects and wrapping material



Dec. 30, 1969 P. A. VAN DE BILT 3,

APPARATUS FOR ASSOCIATING OBJECTS AND WRAPPING MATERIAL Filed Dec. 22,1966 2 Sheets-Sheet 1 Fig"... l

Ullhn m Ei-I-El INVENTOR BY 1* 8M ATTORNEYS Dec. 30, 1969 P. A. VAN DEBILT APPARATUS FOR ASSOCIATING OBJECTS AND WRAPPING MATERIAL 2Sheets-Sheet 2 Filed Dec. 22, 1966 BRAKE INVENTOR r9: 7-5/2 file/v01 aas VAl/JE 6/4 7 ATTORNEYS United States Patent 3,486,293 APPARATUS FORASSOCIATING OBJECTS AND WRAPPING MATERIAL lPieter Arnoldus van de Bilt,Huis Ter Heide, Netherlands, assignor to Metaverpa N.V. Maartensdijk,Netherlands Filed Dec. 22, 1966, Ser. No. 603,803 Claims priority,application Netherlands, Jan. 5, 1966, 6600102 Int. Cl. B651) 41/16,57/12, 61/06 US. Cl. 53-66 8 Claims ABSTRACT OF THE DISCLOSURE Sheets ofwrapping material and objects to be Wrapped in the sheets are fedtogether by apparatus that cuts the sheets to the right length dependingon the length of the object to be Wrapped. Feed rolls are positionedupstream and downstream from the cutting blade, and the advancing objectactuates a brake for the upstream feed rolls. When the upstream feedrolls are braked, the tension in the strip increases, and this actuatesthe cutter. The tensioned strip springs free from the blade. The feedrolls are staggered for centering the strip. If the object to be wrappedis originally stacked, then relatively low-speed feed rolls feed one byone from the bottom of the stack to a relatively high-speed conveyorbelt to space the articles apart.

The present invention relates to apparatus for associating an object tobe wrapped and an appropriate length of wrapping material with eachother, so that the wrapping material can be disposed about the object tobe Wrapped. The object to be wrapped may be a stack of individualobjects, a package, or any other object. The wrapping material can be inthe form of a sheet which covers or encloses the object to be wrapped,about which a wire or tape or rope can be subsequently passed or not, orit can be a length of wrapping material which is itself to be disposedabout another packaging material that encloses the object.

The apparatus of the present invention is characterized by means foradvancing an indeterminate length of wrapping material and for severingthe wrapping material into separate lengths, at the same time that theobject to be wrapped is also advanced, and the severing of theassociated length of Wrapping material is controlled by the advance ofthe object to be wrapped.

Various devices of this type have already been proposed. In U.S. Patent3,001,352, there is disclosed an apparatus for feeding a sheet to thebottom of a stack, in which feeding rollers under the control of aswitch pull the sheet off a supply roll and feed it to a worktable wherethe sheet is drawn along by the front edge of the stack under theimpetus of belt conveyors. The sheet is cut from the supply by means ofa cutting mechanism that operates a certain time after the switch istripped. However, apparatus such as this has the drawback that sheets ofonly a single length can be supplied, and that these sheets are drawnfrom the supply by the object itself.

In US. Patent 2,803,930, there is disclosed an apparatus in which thelength of the sheet is determined by a measuring roll that feeds thesheet. After a given number of revolutions of this roll, the cuttingmechanism is actuated to separate the sheet from the supply. Again,however, only one length of sheet can be supplied.

These known devices also suffer from the disadvantage that the edges ofthe cut material tend to stick to the blade, so that the further feed ofthe Web is impeded.

These known devices have the further disadvantage that sheets can be fedonly to the bottom of the object to be 3,486,293 Patented Dec. 30, 1969packaged, it not being possible with these devices to feed sheets to thetop where such a protective sheet may be equally necessary. For the feedof a sheet to the top, there is however apparatus that operates ondifferent principles, as in US. Patent 3,026,659. In the device of thislatter patent, the uppermost sheet from a stack of previously cut sheetsis fed by means of suction devices, conveyor members, and hold-downmembers to the top of the object to be wrapped.

Accordingly, it is an object of the present invention to provideapparatus as described above, which can feed any desired length ofmaterial, dependent upon the physical characteristics of the object tobe wrapped.

It is also an object of the present invention to provide such apparatus,which can feed lengths of wrapping material either to the top or to thebottom of the object to be wrapped.

Finally, it is an object of the present invention to provide apparatusas described above, which will be relatively simple and inexpensive tomanufacture and install, easy to operate, maintain and repair, andrugged and durable in use.

Other objects and advantages of the present invention will becomeapparent from the following disclosure.

Briefly, the objects of the present invention are achieved in thatbetween a worktable and a cutting blade for the packaging material thereis provided, in addition to the upstream set of feeding rollers, asecond set of feeding rollers, downstream of the cutter. When theapparatus has been started, these second feeding rollers rotatecontinuously with the same speed as that with which the first rollersare driven. Between these two sets of feeding rollers, in addition tothe cutting device, is a device which responds to tension in the sheetand which, when a given value is exceeded, operates a switch thatactuates the cutting device.

The first set of feeding rollers is driven intermittently according tothe advance of an object to be wrapped, and this intermittent drivepulls a length off a supply roll and starts it toward the worktable.However, the second set of rollers rotates continuously. So when thefirst rollers stop, then the tension in the sheet rises and the switchthat actuates the cutting device is operated and the sheet is cutthrough. After that, the rollers of the second set continue to rotateand feed the sheet positively to the worktable. At the same time,because of this tension in the sheet at at the time of cutting, theedges of the sheet are positively pulled off both sides of the blade andthe tension is relieved by the cutting of the sheet. As a result of thispositive feed by means of the second set of feeding rollers, theapparatus can also be used to feed sheets to the top of the object to bewrapped, because the entrainment of the sheet by the object no longerdepends upon the friction which the object exerts on the sheet. If thearticleadvancing means is a belt conveyor, then it is preferable thatthe belt conveyor be driven at the same linear speed as the peripheralspeed of the second set of feeding rollers, in order that the cut-offwrapping material and the object to be wrapped may meet at the samespeed.

The means responsive to tension in the stretch of wrapping materialbetween the first and second roller means may consist of a bent guidewaybetween the two sets of roller means, the guideway extending in such away that the sheet traverses, between the two sets of roller means, apath which is longer than the shortest path between the sets of rollermeans. At the same time, at least the side of the guideway that facestoward that shortest path is yieldably mounted and is adapted tocooperate with a switch that actuates the cutting device. Of course, assoon as the cutting device has cut the sheet through, then the tensionis relieved and this part of the guideway springs back and the leadingedge of the supply material, from which a length has just been cut off,is drawn back to a point some distance from the cutting device or blade,so that no difficulties arise upon subsequent feed actuation. As theswitch is no longer operated, the cutting device or blade returnsautomatically to its rest position.

The switch for controlling the cutting device can operate the cuttingdevice only when the first set of feeding rollers is stopped. Thus it isensured that the blade is not moved by other conditions that might causetension, such as the inertia of the supply roll. If the cutting deviceis pneumatically operated, as in the illustrated embodiment, then theswitch for controlling the cutting device may be an air valve whichcontrols the position of a control valve in the supply of compressed airto cylinders which move the cutting device such as a blade. Such an airvalve is incorporated in a pneumatic circuit in such a way that pressuremedium can be supplied by this valve only when the first set of feedingrollers is stopped, the compressed air circuit to the cutting device orblade being pressureless when the first set of feeding rollers isdriven.

Of course, the pneumatic controls of the present invention can bereplaced by electric controls or by combined fluid-electric controls.

It is a further feature of the invention that the first set of feedingrollers for the packaging material consists of two wheels which contactthe middle of the material, and the second set consists of two pairs ofwheels which contact it near its edges. During feeding by means ofrollers or sets of Wheels, it is extremely difiicult to ensure that theweb follows a perfectly straight path, as infinitesimal aberrations inthe circumference of the rollers or the positions of the roller shaftsin relation to each other result in continuously increasing deviationsof the 'web. But with the feeding rolls arranged as above, insubstantially threepoint gripping arrangement with the web, anydeviation is automatically corrected after the cutting operation. Infact, the material from the supply roll during the first part of therenewed feed is pulled only by a set of rollers contacting its middle,as a result of which the necessary corrections are easily effected.

In the apparatus of the present invention, the length of the sheet canbe predetermined by varying the length of time during which the firstset of feeding rollers operates. This can be done by providing in theworktable a switch which is actuated by the object to be wrapped, forexample by providing that the forward edge of the object actuates thefirst set of feeding rollers and the rear edge actuates a brake forthese rollers. By means of a control blade carried by the switch, it canbe assured that the feeding rollers supply a length of material which isgreater than is the length of the bottom of the object to be wrapped.

According to another feature of the invention, ahead of the beltconveyor in the working plane of the table, that is, upstream of theconveyor with regard to the direction of travel of the upper or workingrun of the conveyor that advances the object to be wrapped, there areprovided at least two driven rollers, spaced apart in the direction ofbelt travel, these rollers being power driven and the roller farthestfrom the belt having a nonslip surface while the roller between thenonslip roller and the belt has a smooth surface. The peripheral speedof the nonslip roller is substantially lower than the linear speed ofthe upper run of the conveyor belt, while the speed of the smooth rollerlies between those upper and lower speeds. By this means, the separationof consecutive objects is achieved, even if these objects are fed from astack or other closely contiguous supply, because the roller with thenonslip surface slowly feeds the objects to the smooth roller and theconveyor belt .pulls them off the smooth roller at a substantiallygreater speed. In other words, the objects speed up when on the smoothroller, which is why the smooth roller must be smooth and the nonsliproller must be nonslip.

The invention will be more clearly understood in connection with theaccompanying drawings, in which:

FIGURE 1 is a side cross-sectional view showing apparatus according tothe invention;

FIGURE 2 is a top plan view of apparatus according to the invention; and

FIGURE 3 is a fluid circuit diagram of the invention.

Referring now to the drawings in greater detail, there is shownparticularly in FIG. 1 apparatus according to the present invention,comprising a frame 1 that carries a worktable 2 with a horizontalworking surface. A supply roll 3 comprises in the illustrated embodimenta rolled-up web of paper 4 of indeterminate length. Web 4 extends abouta roller 5 which is carried by the end of a lever 6 which iscontinuously yieldably urged into bight-forming relationship by atension spring 7.

A pair of conveyor belts 8 are disposed with their upper or working runsin the plane of worktable 2. These conveyor belts are mounted on pulleys9 and 10, support wheels 11, and idlers 12.

To the right of conveyor belts 8 as seen in FIGS. 1 and 2 are conveyorrollers 13 and 14 which are driven by chains 16 and 17 from pulley 10 sothat rollers 13 rotate with a peripheral speed that is lower than thelinear speed of belts 8, while rollers 14 rotate with a lower peripheralspeed then the rollers 13. Rollers 14 have a nonslip surface and rollers13 have a smooth surface. Because of this difference in speed, aseparation of immediately consecutive objects to be wrapped takes place.In operation, the conveyor members 8, 13 and 14 are continuously driven.

Disposed beneath the conveyor members in the frame 1 is apparatus forfeeding and cutting off sheets of paper from the web 4. This apparatuscomprises a guideway 18, a first set of driven feeding rollers or wheels19, and a second set of feeding rollers 20, as well as a pneumaticallyactuated reciprocating cutter blade 21 or other severing device. Therollers 20 are driven by means of a chain 22 from the shaft of pulleys9, this same chain driving a conveyor roller 23 which is disposed at theend of the apparatus immediately downstream of the mouth of guideway 18.The conveyor belts 8 and the roller 23 and the feeding rollers 20, andthe feeding rollers 19 when they are actuated, are therefore all drivenat the same peripheral or linear velocity, so that a severed sheetemerging from guideway 18 leaves the guideway at the speed of the objectwhich is to be wrapped therein.

Between conveyor belts 8 is disposed a control strip 24 in the form of afeeler mechanically moved by the advancing object. Control strip 24controls the operation of the feeding rollers 19. These feeding rollersoperate as long as the advancing object is in contact with the strip 24.It will be seen that a length of the web 4 which is thus fed by therollers 19 will be equal to the length of the object to be wrapped plusthe length of the strip 24 that contacts the object. By selection of anappropriate length for strip 24, an appropriately long excess ofwrapping material, over and above the length of the object, can beobtained. Moreover, objects of different length can be successively fedand the length of wrapping material will be automatically appropriatelyvaried.

These feed rollers 19 pull the web gripped between them through theguideway 18, the lever 6 pivoting to the left during the first part ofthis movement until the supply roll 3 has lost its rest inertia.

Guideway 18 has a downwardly opening concave portion 25. The lower wallof this portion of the guideway has a resilient lip 26 adapted to engageand operate a switch 27. The web then passes the cutting mechanism andis gripped by the rollers 20.

In operation, the conveyor members on worktable 2 move objects to bewrapped, such as stacks of paper or the like, from the right to the leftas shown in the drawing. The feed of these objects is accelerated fromrollers 14 to rollers 13 to belts 8, so that the objects are separatedfrom each other. Upon passing and actuating the strip 24, the feedrollers 19 are actuated, which guide an uncut portion of web 4 throughguideway 18 through feeding rollers 20.

When the fed object passes from the strip 24, the feeding rollers 19stop while the feeding rollers 20 continue to rotate. The tension of theweb thus increases between the rollers 19 and 20 and the resilient lip26 is drawn downwardly and operates the switch 27. Switch 27 then causesthe feed of fluid under pressure to cylinders 28 which actuate blade 21,which rises and cuts through the paper web 4. The cut-off sheet is thenmoved farther by the rollers 20 and ultimately the roller 23. Theresilient lip 26 springs back and draws the forward end of the remainderof the web back from the blade, so that when the web is next advanced bythe rollers 19, the leading edge can pass without difiiculty through theguideway near the cutting mechanism. The rollers 19 are chain drivenfrom rollers 20 through a pneumatically operated clutch while apneumatically controlled brake provides for stopping the rollers 19 whenthe clutch is disengaged.

The fluid pressure circuit for the apparatus of the present invention isshown diagrammatically in FIG. 3. Fluid under pressure, which in theillustrated embodiment is air but could be a liquid, is fed through thepipe 29 from a source of pressure fluid (not shown) and through apressure-reducing valve 32, and thence to a pneumatically operated spoolvalve 30. In the illustrated position of valve 30, air under reducedpressure through a branch conduit 31 maintains valve 30 in a position inwhich the air is fed to cylinders 28 of blade 21 in a direction tomaintain the blade lowered or retracted from the path of the web.

A pneumatic cylinder 33 operates the brake and clutch in alternatepositions thereby to stop or drive rollers 19, respectively. A spoolvalve 34 controls the feed of compressed air to cylinder 33 and, in theposition shown in the drawing, the cylinder 33 is in the position inwhich the rollers 19 are braked. Valve 34 in this position also feedscompressed air through conduit 35 to the valve operated by switch 27which, in the drawing, is in the inactive position. Valve 34 is alsoacted upon by the relatively low pressure in the conduit 31.

When an object to be wrapped passes the strip 24, the associated valveis actuated from the position shown in FIG. 3 to a lower position.Compressed air from conduit 29 is then fed to spool valve 34 so as tomove it from the position shown in FIG. 3 to the other position, becausethe pressure in conduit 29 is higher than the reduced pressure inconduit 31. Cylinder 33 is thus actuated to engage the clutch to driverollers 19.

The upward movement of valve 34 also vents conduit 35, so that movementof the switch 27 during this condition of the parts will have no eflfectat all. Therefore, if for example the supply roll resists turning andthe tension rises in the advancing web between the rollers 19 and 20,the corresponding operation of the switch 27 will have no effect and theblade 21 will remain at rest. It is only when the advancing object hasreleased the strip 24 and the latter returns to the position shown inFIG. 3, as does the valve 34 and the cylinder 33, that the conduit 35 isagain supplied with compressed air, and actuation of of switch 27 underthe influence of the increased tension resulting from the uncoupling andbraking of the rollers 19 will shift the spool valve 30 to the upperposition of FIG. 3, in which the blade 21 is raised to sever a sheet.After the sheet is severed, the tension in the web immediatelydisappears, so that switch 27 returns to its original or raisedposition, as does also the valve 30, so that the blade 21 is immediatelyreturned to its lower position.

From a consideration of the foregoing disclosure, there fore, it will beevident that all of the initially recited objects of the presentinvention have been achieved.

Although the present invention has been described and illustrated inconnection with a preferred embodiment, it is to be understood thatmodifications and variations may be resorted to without departing fromthe spirit of the invention, as those skilled in this art will readilyunderstand. Such modifications and variations are considered to bewithin the purview and scope of the present invention as defined by theappended claims.

Having described my invention, I claim:

1. Apparatus for associating an object to be wrapped and an appropriatelength of Wrapping material, comprising conveyor means for advancing anobject to be wrapped, means for advancing an indeterminate length ofwrapping material, means for severing the wrapping material intoseparate lengths, said wrapping material advancing means comprisingfirst feed roll means upstream of the severing means and second feedroll means downstream of the severing means with regard to the directionof travel of the wrapping material for feeding the wrapping materialpast the severing means, means responsive to the position of a portionof the advancing object to stop the rotation of the first feed rollmeans with the first feed roll means in contact with the wrappingmaterial while the second feed roll means continue to rotate in contactwith the wrapping material thereby to increase the tension in thewrapping material between the first and second feed roll means, meansdeflecting the path of said wrapping material between said first andsecond roll means from the shortest path between said first and secondroll means, and means responsive to movement of said wrapping materialtoward said shortest path to actuate said severing means.

2. Apparatus as claimed in claim 1, said deflecting means comprising abent guideway between said first and second roll means and along whichsaid wrapping material traverses a path longer than the shortest pathbetween said first and second roll means, and means movably supportingat least the side of the guideway that faces said shortest path, saidactuating means comprising switch means responsive to movement of saidguideway side.

3. Apparatus as claimed in claim 2, said severing means comprising ablade, fluid pressure means for moving the blade, said means comprisinga valve to control the supply of pressure fluid to said blade-movingmeans.

4. Apparatus as claimed in claim 1, and means permitting actuation ofsaid severing means only when said rotation-stopping means has beenactuated.

5. Apparatus as claimed in claim 1, said conveyor means including aconveyor belt, and means for driving said conveyor belt at the samelinear speed as the peripheral speed of said second feed roll means.

6. Apparatus for associating an object to be wrapped and an appropriatelength of wrapping material, comprising conveyor means for advancing anobject to be wrapped, means for advancing an indeterminate length ofwrapping material, means for severing the wrapping material intoseparate lengths, said wrapping material advancing means comprisingfirst feed roll means upstream of the severing means and second feedroll means downstream of the severing means with regard to the directionof travel of the wrapping material for feeding the wrapping materialpast the severing means, means responsive to the position of a portionof the advancing object to stop the rotation of the first feed rollmeans with the first feed roll means in contact with the wrappingmaterial while the second feed roll means continue to rotate in contactwith the wrapping material thereby to increase the tension in thewrapping material between the first and second feed roll means, andmeans responsive to said increase in tension to actuate said severingmeans, said conveyor means including a conveyor belt, and means fordriving said conveyor belt at the same linear speed as the peripheralspeed of said second feed roll means, said conveyor belt having anobject-supporting upper run, and driven conveyor rolls upstream and inthe plane of said active run and spaced apart in the direction ofmovement of the object along the conveyor belt, the driven rolls nearestthe conveyor belt having a smooth surface and the driven rolls farthestfrom the conveyor belt having a nonslip surface, and means for drivingthe nonslip rolls at a substantially lower peripheral speed than thelinear speed of the conveyor belt and for driving the smooth surfacedrolls at a peripheral speed intermediate the latter two speeds.

7. Apparatus for associating an object to be wrapped and an appropriatelength of wrapping material, comprising conveyor means for advancing anobject to be wrapped, means for advancing an indeterminate length ofwrapping material, means for severing the wrapping material intoseparate lengths, said wrapping material advancing means comprisingfirst feed roll means upstream of the severing means and second feedroll means downstream of the severing means with regard to the directionof travel of the wrapping material for feeding the wrapping materialpast the severing means, means responsive to the position of a portionof the advancing object to stop the rotation of the first feed rollmeans with the first feed roll means in contact with the wrappingmaterial while the second feed roll means continue to rotate in contactwith the Wrapping material thereby to increase the tension in thewrapping material between the first and second feed roll means, andmeans responsive to said increase in tension to actuate said severingmeans, said first feed roll means comprising a single pair of opposedrolls that contact the middle of the wrapping mate- References CitedUNITED STATES PATENTS 2,227,398 12/1940 Mohl 5366 3,001,352 9/1961Harrison 53-389 3,250,052 5/1966 Hyer 5366 3,250,053 5/1966 Hyer 53-663,262,241 7/1966 Hyer 53-74 X 3,296,768 1/ 1967 Lotz 5374 WAYNE A.MORSE, JR., Primary Examiner US. Cl. X.R. 5374

